What is claimed is:
1. A compound of formula (1)
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wherein R1 and R2 are independently hydrogen or an alkanoyl group of 2-20 carbons.
2. A compound of formula (2)
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wherein X is halogen.
3. A compound of claim 2 wherein X is Br.
4. A compound of formula (3)
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wherein X is halogen and Y is a protecting group.
5. A compound of claim 4 wherein X is Br and Y is t-butyldimethylsilyl.
6. A compound of formula (4)
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wherein X is halogen and Y is a protecting group.
7. A compound of claim 6 wherein X is Br and Y is t-butyldimethylsilyl.
8. A compound of formula (5)
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wherein X is halogen and Y is a protecting group.
9. A compound of claim 8 wherein X is Br and Y is t-butyldimethylsilyl.
10. A compound of formula (6)
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wherein Y is a protecting group.
11. A compound of claim 10 wherein Y is t-butyldimethylsilyl.
12. A compound of formula (7)
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wherein Y is a protecting group.
13. A compound of claim 12 wherein Y is t-butyldimethylsilyl.
14. A compound of formula (8)
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wherein Y is a protecting group.
15. A compound of claim 14 wherein Y is t-butyldimethylsilyl.
16. A compound of formula (9)
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wherein Y is a protecting group.
17. A compound of claim 16 wherein Y is t-butyldimethylsilyl.
18. A compound of formula (10)
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wherein Y is a protecting group.
19. A compound of claim 18 wherein Y is t-butyldimethylsilyl.
20. A process for preparing an optically active compound of formula (1)
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which comprises subjecting a racemic compound of formula (1)
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to a transesterification with an acylating agent in the presence of a hydrolase to optically resolve the racemic compound into an optically active diester of formula (12)
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wherein R3 is an alkyl group of 1-19 carbons, and a monoester of formula (13)
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wherein R3 is as defined above, followed by alcoholysis.
21. A process of claim 20 wherein the acylating agent is a fatty acid vinyl ester.
22. A process of claim 20 wherein the hydrolase is originated from pseudomonas.
23. A process of claim 20 wherein the acylating agent is a fatty acid vinyl ester and the hydrolase is originated from pseudomonas.
24. A process for the preparation of neplanocin A which comprises the steps of:
(a) reacting a compound of formula (1)
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with a halogenating agent, to form a compound of formula (2)
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wherein X is halogen;
(b) reacting the compound (2) with an agent for the protection of hydroxyl groups, to form a compound of formula (3)
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wherein X is as defined above and Y is a protecting group;
(c) treating the compound (3) with an oxidizing agent, to form a compound of formula (4)
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wherein X and Y are as defined above;
(d) reacting the compound (4) with a ketalizing agent, to form a compound of formula (5)
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wherein X and Y are as defined above;
(e) treating the compound (5) with a dehalogenating agent, to form a compound of formula (6)
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wherein Y is as defined above;
(f) subjecting the compound (6) to a retro-Diels-Alder reaction, to form a compound of formula (7)
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wherein Y is as defined above;
(g) treating the compound (7) with an oxidizing agent, to form a compound of formula (8)
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wherein Y is as defined above;
(h) reducing the compound (8) with a reducing agent, to form a compound of formula (9)
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wherein Y is as defined above;
(i) subjecting the compound (9) to a Mitsunobu reaction, to form a compound of formula (10)
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wherein Y is as defined above, followed by deprotection.
25. A process for preparing a compound of formula (7)
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wherein Y is a protecting group, which comprises subjecting a compound of formula (6)
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wherein Y is a protecting group, to a retro-Diels-Alder reaction.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A turbomachine, comprising:
a compressor;
a first shaft;
a second shaft;
a first turbine; and
a second turbine,
the first shaft carrying at least one turbine wheel belonging to one of the first turbine,
the second shaft carrying at least one turbine wheel belonging to the second turbine,
the first and second shafts being oriented substantially vertically in normal utilization situations of the turbomachine, and
the first shaft being held by a first single bearing while the second shaft is held by a second single bearing.
2. The turbomachine according to claim 1, wherein the first shaft and the second shaft are coaxial.
3. The turbomachine according to claim 2, wherein the first shaft passes inside the second shaft.
4. The turbomachine according to claim 3, further comprising a hot zone,
wherein the first and second single bearings are located outside said hot zone.
5. The turbomachine according to claim 3, further comprising a combustion chamber,
wherein the first and second single bearings are located upstream from said combustion chamber.
6. The turbomachine according to claim 4, further comprising a combustion chamber,
wherein the first and second single bearings are located upstream from said combustion chamber.
7. The turbomachine according to claim 3, wherein the first and second single bearings are located upstream from the compressor.
8. An aircraft turbojet, comprising:
the turbomachine according to claim 1.
9. A turboshaft engine, comprising:
the turbomachine according to claim 1.